This invention is in the field of grease rams and an example is U.S. Pat. No. 1,496,104, issued to A. R. Seldon, June 3, 1924, and entitled BEARING CLEANER. In this patent a ram piston having a smaller forward end and a larger rearward end was employed and the body for the ram had a port for admission of grease but had bulkiness because the grease came from a large reservoir attached to the side of the ram.
U.S. Pat. No. 1,579,653 was issed to P. R. Dieringer on Apr. 6, 1926, titled BEARING OBSTRUCTION EJECTOR. In this patent the piston had only one diameter without a smaller forward portion for multiplying power. The body had a grease insert port provided with a ball check fitting attached to it and to which a grease gun could be applied. However, the fitting was very bulky.
Dieringer intended that a hammer blow be struck to remove his piston.
U.S. Pat. No. 1,932,796 was issued to N. F. McNaught on Oct. 31, 1933, and entitled GREASE RAM.
In this patent an impact head for receiving a hammer blow was the ramming force, but the piston had only one diameter and there was no grease input fitting in the side of the body.
U.S. Pat. No. 1,951,503 was issued to J. L. Creveling Mar. 20, 1934, entitled LUBRICATION DEVICE. This device had a piston with a larger rearward portion and a smaller forward portion. Although the larger piston action could be driven with power from a screw thread on the piston, yet the forward portion was only slidable with respect thereto and at its rearward end was a handle with no concept of the application of great force, such as by a hammer blow.
U.S. Pat. No. 3,447,548 was issued to A. R. Perkins on June 3, 1969 and titled PUMP FOR CLEARING AN OIL PASSAGE. In this patent only a single piston outermost diameter was used and striking with a mallet was suggested.
However, in all of these patents above mentioned, there was none to solve the very important problem that has plagued this type of product. The problem is that when an impact force is applied to a ram, the grease fitting on a machine, commonly called a zerk, is often damaged because the force applied against it is quite great.
To my knowledge no solution has been proposed to the immense amount of damage that has occurred using grease rams without protectors for the target zerks, though the amount of damage would be much greater if grease rams had been otherwise designed effectively since if they had been more effective there would have been more attempts to use them.
A particular object of this invention is to provide a grease ram forward part which is a zerk-gripping snap-on fitting such as is used on grease guns which are already in mass production so that low-cost manufacture is possible. The zerk is firmly gripped around the back side of its larger outer portion so that the force of the ramming does not tend to cause the ram to be pushed away from the zerk by the force of the grease. None of the prior art patents have this and very little force can be applied to the body of a grease ram only manually.
An object of this invention is to provide a ram which can be filled with grease from an ordinary grease gun so that before ramming begins there is already great pressure inside the ram. Then when the impact force is applied, the pressure rises much higher, whereby grease that is stuck and clogged in the bearing can be rammed loose with surprising effectiveness.
A particular object is to provide a ram which can apply a force of great magnitude without damaging the zerk, by adjusting a protector to a desired position of protrusion from the body of the ram so as to engage the surface surrounding the target zerk so it, and not the target zerk absorbs the ramming force.
A problem comes in the undesired bending of ram-plungers.
It has been discovered that this bending happens because hammer blows are sometimes on the edge of the plunger head. A solution provided herein is to round the head of the plunger as was discovered to surprisingly help prevent this problem.